It quite often appears following rainfall at the start of the drying process, as the outline of the block shows the differing levels of absorbency of the masonry and its bedding mortar.
In order to prevent ghosting, careful consideration should be given to what thickness of render is used.
The location, orientation and surrounding environment of the building to be rendered, as well as exposure to wind and rain, along with potential protection from surrounding buildings all have an impact on the thickness required to protect the build.
For sheltered to moderate exposure, the minimum recommended thickness of render is 15mm, and this rises to 20mm in the case of severe exposure.
The visual impact of ghosting is worsened in new construction, if the building components have not dried out fully.
If this is the case, the effect should lessen over time – Saint-Gobain Weber recommend leaving the render for a couple of months, in the hope once the blocks are fully dry, and the render fully cured, ghosting will no longer be issue.
If after waiting, the problem persists, there are two options to remedy it…
A high-performance, water-resistant paint, such as webersil P, may be applied to the building to overcome the issue of ghosting. webersil P is a mineral paint with exceptional long-term durability and performance, and comes in a range of 160 colours. This paint is suitable for use with our weberpral renders, provided the elevation is clean, sound and dry.
In some circumstances, it may be advisable that rather than painting, the thickness of the render should be increased.
Before re-rendering, the entire area to be rendered should be stripped of any paint or coating, and should be clean, dry and sound.
If necessary, a coat of weber CL150 can be used to ensure no algae is present on the surface. A keycoat of weberend aid should be applied, followed by a pass of weberpral M (or weberpral D in Ireland) render at 10mm which is scraped back to a thickness of 6mm.
As with any project, Saint-Gobain Weber will be with you every step of the way. If you’ve unexpectedly experienced ghosting, the company is happy to advise on how best to deal with the issue.
Saint-Gobain Weber
Dickens House, Enterprise Way
Maulden Road
Flitwick
Bedford
MK45 5BY
UK
Visit Saint-Gobain Weber's website
A rundown office and warehouse building completely transformed into a modern headquarters for Atlas Copco has been fitted with more than 120 internal fire doors from Enfield Speciality Doors.
Posted in Access Control & Door Entry Systems, Articles, Building Industry News, Building Products & Structures, Building Systems, Case Studies, Doors, Interior Design & Construction, Interiors, Posts, Restoration & Refurbishment, Retrofit & Renovation, Security and Fire Protection, Sustainability & Energy Efficiency, Timber Buildings and Timber Products, Wooden productsAbloy UK, a leading provider of security and access control solutions, has launched a new white paper.
Posted in Access Control & Door Entry Systems, Architectural Ironmongery, Articles, Building Industry News, Building Products & Structures, Building Services, Doors, Facility Management & Building Services, Health & Safety, Information Technology, Innovations & New Products, Publications, Research & Materials Testing, Security and Fire ProtectionDavid Roy of MCRMA member company Roofconsult has more than 50 years’ experience to draw upon working in the building envelope sector and a unique perspective on how it has changed in that time.
Posted in Articles, BIM, Infrastructure & CAD Software, Building Associations & Institutes, Building Industry News, Building Products & Structures, Building Services, Building Systems, Cladding, Information Technology, Restoration & Refurbishment, Retrofit & Renovation, Roofs, WallsCraig Fox, Sales Director for Strand Hardware, outlines how door industry professionals might apply door limiting stays…
Posted in Architectural Ironmongery, Articles, Building Industry News, Building Products & Structures, Building Services, Doors, Facility Management & Building Services, Health & Safety, Restoration & Refurbishment, Retrofit & Renovation